The Japanese arm of the World Wide Fund for Nature urged Yahoo Japan Corp. on Thursday to impose tighter restrictions on the trade of ivory items on its auction site, saying it serves as a major venue for ivory trade and encourages poaching.Among other major e-commerce companies in the country, trading of ivory items has disappeared on the site of Rakuten Inc. and sharply declined on Mercari Inc.'s community marketplace app after they banned ivory sales, according to a recent survey by WWF Japan.The survey conducted between June and July found ivory items worth 37.8 million yen ($340,000) w…READ FULL ARTICLE